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E39 (1997 - 2003) The BMW 5-Series (E39 chassis) was introduced in the United States as a 1997 model year car and lasted until the 2004 when the E60 chassis was released. The United States saw several variations including the 525i, 528i, 530i and 540i. -- View the E39 Wiki

If your carfull you can remove the distribution piece without breaking anything. Doru, you just changed your CVV and hose not long ago. You shouldn't have any trouble to clean the distribution unit. The way I clean it, is to remove the part using a very long screw driver to pry up gently at each port front to back. I use throttlbody
cleaner and spray into each port slowly until the whole of the body is full. Walk away afterwards and let the part soak for about 10 min and then come back and use some compressed air to get the junk thats in the part out. Of course have some new 0 rings ready to replace the old parts on the DU.
On checking the DU for vac leaks, you would be surprised how many told me I would hydrolock my engine
by having a few drops of water introduced to the combustion chamber from my methods mentioned.

Thank you guys. I need to change the injector O-rings/clean the injectors as well, so I might clean the distribution piece as well. I noticed some heavy mayo on my dipstick (argh!) so there is some gunk in there for sure. I know I did the CCV about 2 years ago, but after seeing all that mayo last week on my dipstick, I just wonder......

P.S. : if judging by approach: leave some brake cleaner in the distribution piece for a while to dissolve the gunk inside would work also for the CCV? Or will the brake cleaner damage the diaphragm?

The original M54 DISA O-ring apparently has a rectangular cross section.

But, if I understand the fix here, you guys are replacing the rectangular o-ring with a circular cross section o-ring. Is that right?

And, what about the 'vertical sealing strips' (which are shown in the photo I previously posted from this thread)?
- Engine code po171

Are people fixing the vertical strips also?

Quote:

Originally Posted by pshovest

No one had proposed an oring solution when I had the problem and I'm not convinced the oring fix is the best. The M52TU uses an oring, but the M54 DISA seal is not an oring. It is a molded part that doesn't have a round cross section. If the replacement oring is too thick, the DISA won't be properly seated and sealed in the intake manifold. Notice the two vertical sealing strips on the DISA in the photo? The Form-a-gasket fix is less likely to interfere with these seals.

Is this guy who is selling Oring on ebay trust worthy? I've ordered the oring on 14th may and mailed him 2 times but no response or oring yet. I even didn't get any confirmation or mail from him for delivery too. What you guys think of him?

Is this guy who is selling Oring on ebay trust worthy? I've ordered the oring on 14th may and mailed him 2 times but no response or oring yet. I even didn't get any confirmation or mail from him for delivery too. What you guys think of him?

Vacuum from the engine would pull the silicone into the cylinders. Now if your smart and use sensor safe silicone there wouldn't be any problem. The only problem with small bits of silicone getting into the cylinders would be that once burned the stuff would contaminate your 02 sensors. The stuff is so sofet that there wouldn't a problem to the combustion chamber, unless your pour huge amounts in. For the amount thats going to be used to seal off the DISA valve, only small and I mean very small particles would be pulled into the engine. I don't see where this would cause any problems what so ever.

Vacuum from the engine would pull the silicone into the cylinders. Now if your smart and use sensor safe silicone there wouldn't be any problem. The only problem with small bits of silicone getting into the cylinders would be that once burned the stuff would contaminate your 02 sensors. The stuff is so sofet that there wouldn't a problem to the combustion chamber, unless your pour huge amounts in. For the amount thats going to be used to seal off the DISA valve, only small and I mean very small particles would be pulled into the engine. I don't see where this would cause any problems what so ever.

if you use the sealant that is not sensor safe, you will end up like this.

The picture shown here is a silicone contaminated oxygen sensor. A contaminated O2 sensor will give you lean fuel-air mixture and the car feels very sluggish. You might not get a code but you will get a bad gas mileage.

Is the O-ring on M54 DISA units just an O-ring or more complicated? Has anyone measured that one?

Technically, there is no O-Ring on the M54 DISA units... and that's why there is not one shown on the realoem diagrams. The sealing is done via a built-in "lip" on the base of the unit that mimics an o-ring. Yes, you can gouge out the old sealing to uncover the grove that a normal o-ring can be fitted into, but you have to wonder why BMW made it the way they did, why it's rectangular, and the original seal is moulded and "glued" into place.

Also, and a big assumption here - the reason the DISA units may not have a traditional o-ring fitted, is, what might happen when it wears, or is mis-fitted, and gets sucked down the intake manifold and into the motor?

Putting an o-ring onto an old worn unit might be a bit of a risk perhaps.

Attached Thumbnails

Last edited by Bazza-Aus; 09-30-2011 at 09:41 PM.
Reason: Attached pics of old DISA Vs new DISA